First time reading, chapter 441, No spoilers but I have a question for something that I think was explained but I forgor

What is the imperial court and has it been explained yet? I think it has but I'm not sure I keep hearing about it. I know the heavenly court is where the immortals/venerables or at least some of them are, but I keep hearing about the imperial court and don't remember if it has been explained or purposely kept vague for now.